1. Field of the Invention
The present invention relates to a multi-function control key structure for an electronic device, for example, a computer, video cassette player/recorder, remote controller, etc.
2. Description of Related Art
An electronic consumer product may be provided with a so-called multi-function key assembly, which has a button exposed to the outside for multiple function controls, for example, up, down, left, right controls.
Regular multi-function key assemblies include two types, namely, the so-called 4-in-1 and the so-called 5-in-2. A 4-in-1 multi-function key assembly provides up, down, left, and right control functions. If an electronic device needs more than four control functions, a 4-in-1 multi-function key assembly cannot meet the requirement. Further, a 5-in-2 multi-function key assembly comprises an outer key unit and a center key unit. The outer key unit provides up, down, left, right controls. The center key is for another function control. A 5-in-2 multi-function key assembly settles the insufficient function control problem of a 4-in-1 multi-function key assembly, however the additional center key unit greatly complicates the manufacturing process and increases the manufacturing cost.
Further, U.S. Pat. No. 6,441,753 discloses a multi-function key assembly for electronic device. This design of multi-function key assembly is applicable for 8 different function controls. However, this design of multi-function key assembly uses a big number of parts. Further, the button of this design of multi-function key assembly may not return to its former position after having been pressed,